jj.http.server.websocket.WebSocketConnectionMaker.java Source code

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Here is the source code for jj.http.server.websocket.WebSocketConnectionMaker.java

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/*
 *    Copyright 2012 Jason Miller
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package jj.http.server.websocket;

import static jj.http.server.PipelineStages.*;

import java.util.Set;

import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.handler.codec.http.FullHttpRequest;
import io.netty.handler.codec.http.HttpResponseStatus;
import io.netty.handler.codec.http.HttpHeaders.Names;
import io.netty.handler.codec.http.websocketx.CloseWebSocketFrame;
import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import io.netty.handler.codec.http.websocketx.WebSocketHandshakeException;
import io.netty.handler.codec.http.websocketx.WebSocketServerHandshaker;
import io.netty.handler.codec.http.websocketx.WebSocketServerHandshakerFactory;
import io.netty.handler.codec.http.websocketx.WebSocketVersion;

import javax.inject.Inject;
import javax.inject.Singleton;

import jj.configuration.resolution.AppLocation;
import jj.http.server.HttpServerResponse;
import jj.http.uri.URIMatch;
import jj.resource.ResourceFinder;

/**
 * @author jason
 *
 */
@Singleton
public class WebSocketConnectionMaker {

    private final WebSocketFrameHandlerCreator handlerCreator;

    private final ResourceFinder resourceFinder;

    private final ChannelHandlerContext ctx;

    private final FullHttpRequest request;

    private final HttpServerResponse response;

    private final WebSocketServerHandshakerFactory handshakerFactory;

    private final Set<Class<? extends WebSocketConnectionHost>> webSocketConnectionHostClasses;

    @Inject
    WebSocketConnectionMaker(final WebSocketFrameHandlerCreator handlerCreator, final ResourceFinder resourceFinder,
            final ChannelHandlerContext ctx, final FullHttpRequest request, final HttpServerResponse response,
            final WebSocketServerHandshakerFactory handshakerFactory,
            final Set<Class<? extends WebSocketConnectionHost>> webSocketConnectionHostClasses) {
        this.handlerCreator = handlerCreator;
        this.resourceFinder = resourceFinder;
        this.ctx = ctx;
        this.request = request;
        this.response = response;
        this.handshakerFactory = handshakerFactory;
        this.webSocketConnectionHostClasses = webSocketConnectionHostClasses;
    }

    public void handshakeWebsocket() {
        final WebSocketServerHandshaker handshaker = handshakerFactory.newHandshaker(request);
        if (handshaker == null) {
            response.header(Names.SEC_WEBSOCKET_VERSION, WebSocketVersion.V13.toHttpHeaderValue())
                    .sendError(HttpResponseStatus.UPGRADE_REQUIRED);
        } else {
            doHandshake(ctx, request, handshaker);
        }
    }

    private void doHandshake(final ChannelHandlerContext ctx, final FullHttpRequest request,
            final WebSocketServerHandshaker handshaker) {
        handshaker.handshake(ctx.channel(), request).addListener(new ChannelFutureListener() {

            private boolean isHandshakeFailure(ChannelFuture future) {
                return future.cause() != null && future.cause() instanceof WebSocketHandshakeException;
            }

            @Override
            public void operationComplete(ChannelFuture future) throws Exception {
                if (future.isSuccess()) {

                    URIMatch uriMatch = new URIMatch(request.getUri());

                    WebSocketConnectionHost host = null;

                    for (Class<? extends WebSocketConnectionHost> hostClass : webSocketConnectionHostClasses) {
                        host = resourceFinder.findResource(hostClass, AppLocation.Virtual, uriMatch.name);
                        if (host != null)
                            break;
                    }

                    if (host == null) {

                        // 1011 indicates that a server is terminating the connection because
                        // it encountered an unexpected condition that prevented it from
                        // fulfilling the request.
                        ctx.writeAndFlush(new CloseWebSocketFrame(1011, null)).addListener(CLOSE);
                        // TODO: is closing here the right thing? or do we count on the client closing the connection
                        // to avoid the time_wait state? 

                    } else if (!uriMatch.sha1.equals(host.sha1())) {

                        ctx.writeAndFlush(new TextWebSocketFrame("jj-reload"))
                                .addListener(new ChannelFutureListener() {

                                    @Override
                                    public void operationComplete(ChannelFuture future) throws Exception {
                                        // 1001 indicates that an endpoint is "going away", such as a server
                                        // going down or a browser having navigated away from a page.
                                        ctx.writeAndFlush(new CloseWebSocketFrame(1001, null)).addListener(CLOSE);
                                        // TODO: is closing here the right thing? or do we count on the client closing the connection
                                        // to avoid the time_wait state? 
                                    }
                                });

                    } else {

                        ctx.pipeline().replace(JJEngine.toString(), JJWebsocketHandler.toString(),
                                handlerCreator.createHandler(handshaker, host));
                    }

                } else if (isHandshakeFailure(future)) {
                    response.sendError(HttpResponseStatus.BAD_REQUEST);
                } else {
                    ctx.close();
                }
            }
        });
    }
}